反应详情

A mixture of (3aS,4S,6R,6aR)-6-(6-isopropylamino-purin-9-yl)-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxole-4-carboxylic acid (4.82 g) and 2-ethoxy-N-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ, 3.36 g) in methanol (150 ml) was heated under reflux for 60 h. After cooling to room temperature, the solution was concentrated in vacuo and the resulting residue partitioned between ethyl acetate (100 ml) and citric acid solution (0.5M, 75 ml). The aqueous layer was extracted with ethyl acetate (4×25 ml) and the combined organic extracts were washed with water (50 ml) and brine (75 ml), dried (MgSO4), filtered and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica gel, eluting with ethyl acetate: cyclohexane (1:1) to afford the title compound as a white solid (3.76 g).

1. temperaturewas heated
2. temperatureunder reflux for 60 h
3. concentrationthe solution was concentrated in vacuo
4. customthe resulting residue partitioned between ethyl acetate (100 ml) and citric acid solution (0.5M, 75 ml)
5. extractionThe aqueous layer was extracted with ethyl acetate (4×25 ml)
6. washthe combined organic extracts were washed with water (50 ml) and brine (75 ml)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe resulting residue was purified by flash chromatography on silica gel
11. washeluting with ethyl acetate: cyclohexane (1:1)